/* * (C) 2001-2004 Dave Jones. * (C) 2002 Padraig Brady. * * Licensed under the terms of the GNU GPL License version 2. * Based upon datasheets & sample CPUs kindly provided by VIA. * * VIA have currently 3 different versions of Longhaul. * Version 1 (Longhaul) uses the BCR2 MSR at 0x1147. * It is present only in Samuel 1 (C5A), Samuel 2 (C5B) stepping 0. * Version 2 of longhaul is backward compatible with v1, but adds * LONGHAUL MSR for purpose of both frequency and voltage scaling. * Present in Samuel 2 (steppings 1-7 only) (C5B), and Ezra (C5C). * Version 3 of longhaul got renamed to Powersaver and redesigned * to use only the POWERSAVER MSR at 0x110a. * It is present in Ezra-T (C5M), Nehemiah (C5X) and above. * It's pretty much the same feature wise to longhaul v2, though * there is provision for scaling FSB too, but this doesn't work * too well in practice so we don't even try to use this. * * BIG FAT DISCLAIMER: Work in progress code. Possibly *dangerous* */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "longhaul.h" #define PFX "longhaul: " #define TYPE_LONGHAUL_V1 1 #define TYPE_LONGHAUL_V2 2 #define TYPE_POWERSAVER 3 #define CPU_SAMUEL 1 #define CPU_SAMUEL2 2 #define CPU_EZRA 3 #define CPU_EZRA_T 4 #define CPU_NEHEMIAH 5 #define CPU_NEHEMIAH_C 6 /* Flags */ #define USE_ACPI_C3 (1 << 1) #define USE_NORTHBRIDGE (1 << 2) static int cpu_model; static unsigned int numscales = 16; static unsigned int fsb; static const struct mV_pos *vrm_mV_table; static const unsigned char *mV_vrm_table; static unsigned int highest_speed, lowest_speed; /* kHz */ static unsigned int minmult, maxmult; static int can_scale_voltage; static struct acpi_processor *pr; static struct acpi_processor_cx *cx; static u32 acpi_regs_addr; static u8 longhaul_flags; static unsigned int longhaul_index; /* Module parameters */ static int scale_voltage; static int disable_acpi_c3; static int revid_errata; static int enable; /* Clock ratios multiplied by 10 */ static int mults[32]; static int eblcr[32]; static int longhaul_version; static struct cpufreq_frequency_table *longhaul_table; static char speedbuffer[8]; static char *print_speed(int speed) { if (speed < 1000) { snprintf(speedbuffer, sizeof(speedbuffer), "%dMHz", speed); return speedbuffer; } if (speed%1000 == 0) snprintf(speedbuffer, sizeof(speedbuffer), "%dGHz", speed/1000); else snprintf(speedbuffer, sizeof(speedbuffer), "%d.%dGHz", speed/1000, (speed%1000)/100); return speedbuffer; } static unsigned int calc_speed(int mult) { int khz; khz = (mult/10)*fsb; if (mult%10) khz += fsb/2; khz *= 1000; return khz; } static int longhaul_get_cpu_mult(void) { unsigned long invalue = 0, lo, hi; rdmsr(MSR_IA32_EBL_CR_POWERON, lo, hi); invalue = (lo & (1<<22|1<<23|1<<24|1<<25))>>22; if (longhaul_version == TYPE_LONGHAUL_V2 || longhaul_version == TYPE_POWERSAVER) { if (lo & (1<<27)) invalue += 16; } return eblcr[invalue]; } /* For processor with BCR2 MSR */ static void do_longhaul1(unsigned int mults_index) { union msr_bcr2 bcr2; rdmsrl(MSR_VIA_BCR2, bcr2.val); /* Enable software clock multiplier */ bcr2.bits.ESOFTBF = 1; bcr2.bits.CLOCKMUL = mults_index & 0xff; /* Sync to timer tick */ safe_halt(); /* Change frequency on next halt or sleep */ wrmsrl(MSR_VIA_BCR2, bcr2.val); /* Invoke transition */ ACPI_FLUSH_CPU_CACHE(); halt(); /* Disable software clock multiplier */ local_irq_disable(); rdmsrl(MSR_VIA_BCR2, bcr2.val); bcr2.bits.ESOFTBF = 0; wrmsrl(MSR_VIA_BCR2, bcr2.val); } /* For processor with Longhaul MSR */ static void do_powersaver(int cx_address, unsigned int mults_index, unsigned int dir) { union msr_longhaul longhaul; u32 t; rdmsrl(MSR_VIA_LONGHAUL, longhaul.val); /* Setup new frequency */ if (!revid_errata) longhaul.bits.RevisionKey = longhaul.bits.RevisionID; else longhaul.bits.RevisionKey = 0; longhaul.bits.SoftBusRatio = mults_index & 0xf; longhaul.bits.SoftBusRatio4 = (mults_index & 0x10) >> 4; /* Setup new voltage */ if (can_scale_voltage) longhaul.bits.SoftVID = (mults_index >> 8) & 0x1f; /* Sync to timer tick */ safe_halt(); /* Raise voltage if necessary */ if (can_scale_voltage && dir) { longhaul.bits.EnableSoftVID = 1; wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); /* Change voltage */ if (!cx_address) { ACPI_FLUSH_CPU_CACHE(); halt(); } else { ACPI_FLUSH_CPU_CACHE(); /* Invoke C3 */ inb(cx_address); /* Dummy op - must do something useless after P_LVL3 * read */ t = inl(acpi_gbl_FADT.xpm_timer_block.address); } longhaul.bits.EnableSoftVID = 0; wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); } /* Change frequency on next halt or sleep */ longhaul.bits.EnableSoftBusRatio = 1; wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); if (!cx_address) { ACPI_FLUSH_CPU_CACHE(); halt(); } else { ACPI_FLUSH_CPU_CACHE(); /* Invoke C3 */ inb(cx_address); /* Dummy op - must do something useless after P_LVL3 read */ t = inl(acpi_gbl_FADT.xpm_timer_block.address); } /* Disable bus ratio bit */ longhaul.bits.EnableSoftBusRatio = 0; wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); /* Reduce voltage if necessary */ if (can_scale_voltage && !dir) { longhaul.bits.EnableSoftVID = 1; wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); /* Change voltage */ if (!cx_address) { ACPI_FLUSH_CPU_CACHE(); halt(); } else { ACPI_FLUSH_CPU_CACHE(); /* Invoke C3 */ inb(cx_address); /* Dummy op - must do something useless after P_LVL3 * read */ t = inl(acpi_gbl_FADT.xpm_timer_block.address); } longhaul.bits.EnableSoftVID = 0; wrmsrl(MSR_VIA_LONGHAUL, longhaul.val); } } /** * longhaul_set_cpu_frequency() * @mults_index : bitpattern of the new multiplier. * * Sets a new clock ratio. */ static int longhaul_setstate(struct cpufreq_policy *policy, unsigned int table_index) { unsigned int mults_index; int speed, mult; struct cpufreq_freqs freqs; unsigned long flags; unsigned int pic1_mask, pic2_mask; u16 bm_status = 0; u32 bm_timeout = 1000; unsigned int dir = 0; mults_index = longhaul_table[table_index].driver_data; /* Safety precautions */ mult = mults[mults_index & 0x1f]; if (mult == -1) return -EINVAL; speed = calc_speed(mult); if ((speed > highest_speed) || (speed < lowest_speed)) return -EINVAL; /* Voltage transition before frequency transition? */ if (can_scale_voltage && longhaul_index < table_index) dir = 1; freqs.old = calc_speed(longhaul_get_cpu_mult()); freqs.new = speed; pr_debug("Setting to FSB:%dMHz Mult:%d.%dx (%s)\n", fsb, mult/10, mult%10, print_speed(speed/1000)); retry_loop: preempt_disable(); local_irq_save(flags); pic2_mask = inb(0xA1); pic1_mask = inb(0x21); /* works on C3. save mask. */ outb(0xFF, 0xA1); /* Overkill */ outb(0xFE, 0x21); /* TMR0 only */ /* Wait while PCI bus is busy. */ if (acpi_regs_addr && (longhaul_flags & USE_NORTHBRIDGE || ((pr != NULL) && pr->flags.bm_control))) { bm_status = inw(acpi_regs_addr); bm_status &= 1 << 4; while (bm_status && bm_timeout) { outw(1 << 4, acpi_regs_addr); bm_timeout--; bm_status = inw(acpi_regs_addr); bm_status &= 1 << 4; } } if (longhaul_flags & USE_NORTHBRIDGE) { /* Disable AGP and PCI arbiters */ outb(3, 0x22); } else if ((pr != NULL) && pr->flags.bm_control) { /* Disable bus master arbitration */ acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 1); } switch (longhaul_version) { /* * Longhaul v1. (Samuel[C5A] and Samuel2 stepping 0[C5B]) * Software controlled multipliers only. */ case TYPE_LONGHAUL_V1: do_longhaul1(mults_index); break; /* * Longhaul v2 appears in Samuel2 Steppings 1->7 [C5B] and Ezra [C5C] * * Longhaul v3 (aka Powersaver). (Ezra-T [C5M] & Nehemiah [C5N]) * Nehemiah can do FSB scaling too, but this has never been proven * to work in practice. */ case TYPE_LONGHAUL_V2: case TYPE_POWERSAVER: if (longhaul_flags & USE_ACPI_C3) { /* Don't allow wakeup */ acpi_write_bit_register(ACPI_BITREG_BUS_MASTER_RLD, 0); do_powersaver(cx->address, mults_index, dir); } else { do_powersaver(0, mults_index, dir); } break; } if (longhaul_flags & USE_NORTHBRIDGE) { /* Enable arbiters */ outb(0, 0x22); } else if ((pr != NULL) && pr->flags.bm_control) { /* Enable bus master arbitration */ acpi_write_bit_register(ACPI_BITREG_ARB_DISABLE, 0); } outb(pic2_mask, 0xA1); /* restore mask */ outb(pic1_mask, 0x21); local_irq_restore(flags); preempt_enable(); freqs.new = calc_speed(longhaul_get_cpu_mult()); /* Check if requested frequency is set. */ if (unlikely(freqs.new != speed)) { printk(KERN_INFO PFX "Failed to set requested frequency!\n"); /* Revision ID = 1 but processor is expecting revision key * equal to 0. Jumpers at the bottom of processor will change * multiplier and FSB, but will not change bits in Longhaul * MSR nor enable voltage scaling. */ if (!revid_errata) { printk(KERN_INFO PFX "Enabling \"Ignore Revision ID\" " "option.\n"); revid_errata = 1; msleep(200); goto retry_loop; } /* Why ACPI C3 sometimes doesn't work is a mystery for me. * But it does happen. Processor is entering ACPI C3 state, * but it doesn't change frequency. I tried poking various * bits in northbridge registers, but without success. */ if (longhaul_flags & USE_ACPI_C3) { printk(KERN_INFO PFX "Disabling ACPI C3 support.\n"); longhaul_flags &= ~USE_ACPI_C3; if (revid_errata) { printk(KERN_INFO PFX "Disabling \"Ignore " "Revision ID\" option.\n"); revid_errata = 0; } msleep(200); goto retry_loop; } /* This shouldn't happen. Longhaul ver. 2 was reported not * working on processors without voltage scaling, but with * RevID = 1. RevID errata will make things right. Just * to be 100% sure. */ if (longhaul_version == TYPE_LONGHAUL_V2) { printk(KERN_INFO PFX "Switching to Longhaul ver. 1\n"); longhaul_version = TYPE_LONGHAUL_V1; msleep(200); goto retry_loop; } } if (!bm_timeout) { printk(KERN_INFO PFX "Warning: Timeout while waiting for " "idle PCI bus.\n"); return -EBUSY; } return 0; } /* * Centaur decided to make life a little more tricky. * Only longhaul v1 is allowed to read EBLCR BSEL[0:1]. * Samuel2 and above have to try and guess what the FSB is. * We do this by assuming we booted at maximum multiplier, and interpolate * between that value multiplied by possible FSBs and cpu_mhz which * was calculated at boot time. Really ugly, but no other way to do this. */ #define ROUNDING 0xf static int guess_fsb(int mult) { int speed = cpu_khz / 1000; int i; int speeds[] = { 666, 1000, 1333, 2000 }; int f_max, f_min; for (i = 0; i < 4; i++) { f_max = ((speeds[i] * mult) + 50) / 100; f_max += (ROUNDING / 2); f_min = f_max - ROUNDING; if ((speed <= f_max) && (speed >= f_min)) return speeds[i] / 10; } return 0; } static int longhaul_get_ranges(void) { unsigned int i, j, k = 0; unsigned int ratio; int mult; /* Get current frequency */ mult = longhaul_get_cpu_mult(); if (mult == -1) { printk(KERN_INFO PFX "Invalid (reserved) multiplier!\n"); return -EINVAL; } fsb = guess_fsb(mult); if (fsb == 0) { printk(KERN_INFO PFX "Invalid (reserved) FSB!\n"); return -EINVAL; } /* Get max multiplier - as we always did. * Longhaul MSR is useful only when voltage scaling is enabled. * C3 is booting at max anyway. */ maxmult = mult; /* Get min multiplier */ switch (cpu_model) { case CPU_NEHEMIAH: minmult = 50; break; case CPU_NEHEMIAH_C: minmult = 40; break; default: minmult = 30; break; } pr_debug("MinMult:%d.%dx MaxMult:%d.%dx\n", minmult/10, minmult%10, maxmult/10, maxmult%10); highest_speed = calc_speed(maxmult); lowest_speed = calc_speed(minmult); pr_debug("FSB:%dMHz Lowest speed: %s Highest speed:%s\n", fsb, print_speed(lowest_speed/1000), print_speed(highest_speed/1000)); if (lowest_speed == highest_speed) { printk(KERN_INFO PFX "highestspeed == lowest, aborting.\n"); return -EINVAL; } if (lowest_speed > highest_speed) { printk(KERN_INFO PFX "nonsense! lowest (%d > %d) !\n", lowest_speed, highest_speed); return -EINVAL; } longhaul_table = kzalloc((numscales + 1) * sizeof(*longhaul_table), GFP_KERNEL); if (!longhaul_table) return -ENOMEM; for (j = 0; j < numscales; j++) { ratio = mults[j]; if (ratio == -1) continue; if (ratio > maxmult || ratio < minmult) continue; longhaul_table[k].frequency = calc_speed(ratio); longhaul_table[k].driver_data = j; k++; } if (k <= 1) { kfree(longhaul_table); return -ENODEV; } /* Sort */ for (j = 0; j < k - 1; j++) { unsigned int min_f, min_i; min_f = longhaul_table[j].frequency; min_i = j; for (i = j + 1; i < k; i++) { if (longhaul_table[i].frequency < min_f) { min_f = longhaul_table[i].frequency; min_i = i; } } if (min_i != j) { swap(longhaul_table[j].frequency, longhaul_table[min_i].frequency); swap(longhaul_table[j].driver_data, longhaul_table[min_i].driver_data); } } longhaul_table[k].frequency = CPUFREQ_TABLE_END; /* Find index we are running on */ for (j = 0; j < k; j++) { if (mults[longhaul_table[j].driver_data & 0x1f] == mult) { longhaul_index = j; break; } } return 0; } static void longhaul_setup_voltagescaling(void) { struct cpufreq_frequency_table *freq_pos; union msr_longhaul longhaul; struct mV_pos minvid, maxvid, vid; unsigned int j, speed, pos, kHz_step, numvscales; int min_vid_speed; rdmsrl(MSR_VIA_LONGHAUL, longhaul.val); if (!(longhaul.bits.RevisionID & 1)) { printk(KERN_INFO PFX "Voltage scaling not supported by CPU.\n"); return; } if (!longhaul.bits.VRMRev) { printk(KERN_INFO PFX "VRM 8.5\n"); vrm_mV_table = &vrm85_mV[0]; mV_vrm_table = &mV_vrm85[0]; } else { printk(KERN_INFO PFX "Mobile VRM\n"); if (cpu_model < CPU_NEHEMIAH) return; vrm_mV_table = &mobilevrm_mV[0]; mV_vrm_table = &mV_mobilevrm[0]; } minvid = vrm_mV_table[longhaul.bits.MinimumVID]; maxvid = vrm_mV_table[longhaul.bits.MaximumVID]; if (minvid.mV == 0 || maxvid.mV == 0 || minvid.mV > maxvid.mV) { printk(KERN_INFO PFX "Bogus values Min:%d.%03d Max:%d.%03d. " "Voltage scaling disabled.\n", minvid.mV/1000, minvid.mV%1000, maxvid.mV/1000, maxvid.mV%1000); return; } if (minvid.mV == maxvid.mV) { printk(KERN_INFO PFX "Claims to support voltage scaling but " "min & max are both %d.%03d. " "Voltage scaling disabled\n", maxvid.mV/1000, maxvid.mV%1000); return; } /* How many voltage steps*/ numvscales = maxvid.pos - minvid.pos + 1; printk(KERN_INFO PFX "Max VID=%d.%03d " "Min VID=%d.%03d, " "%d possible voltage scales\n", maxvid.mV/1000, maxvid.mV%1000, minvid.mV/1000, minvid.mV%1000, numvscales); /* Calculate max frequency at min voltage */ j = longhaul.bits.MinMHzBR; if (longhaul.bits.MinMHzBR4) j += 16; min_vid_speed = eblcr[j]; if (min_vid_speed == -1) return; switch (longhaul.bits.MinMHzFSB) { case 0: min_vid_speed *= 13333; break; case 1: min_vid_speed *= 10000; break; case 3: min_vid_speed *= 6666; break; default: return; break; } if (min_vid_speed >= highest_speed) return; /* Calculate kHz for one voltage step */ kHz_step = (highest_speed - min_vid_speed) / numvscales; cpufreq_for_each_entry(freq_pos, longhaul_table) { speed = freq_pos->frequency; if (speed > min_vid_speed) pos = (speed - min_vid_speed) / kHz_step + minvid.pos; else pos = minvid.pos; freq_pos->driver_data |= mV_vrm_table[pos] << 8; vid = vrm_mV_table[mV_vrm_table[pos]]; printk(KERN_INFO PFX "f: %d kHz, index: %d, vid: %d mV\n", speed, (int)(freq_pos - longhaul_table), vid.mV); } can_scale_voltage = 1; printk(KERN_INFO PFX "Voltage scaling enabled.\n"); } static int longhaul_target(struct cpufreq_policy *policy, unsigned int table_index) { unsigned int i; unsigned int dir = 0; u8 vid, current_vid; int retval = 0; if (!can_scale_voltage) retval = longhaul_setstate(policy, table_index); else { /* On test system voltage transitions exceeding single * step up or down were turning motherboard off. Both * "ondemand" and "userspace" are unsafe. C7 is doing * this in hardware, C3 is old and we need to do this * in software. */ i = longhaul_index; current_vid = (longhaul_table[longhaul_index].driver_data >> 8); current_vid &= 0x1f; if (table_index > longhaul_index) dir = 1; while (i != table_index) { vid = (longhaul_table[i].driver_data >> 8) & 0x1f; if (vid != current_vid) { retval = longhaul_setstate(policy, i); current_vid = vid; msleep(200); } if (dir) i++; else i--; } retval = longhaul_setstate(policy, table_index); } longhaul_index = table_index; return retval; } static unsigned int longhaul_get(unsigned int cpu) { if (cpu) return 0; return calc_speed(longhaul_get_cpu_mult()); } static acpi_status longhaul_walk_callback(acpi_handle obj_handle, u32 nesting_level, void *context, void **return_value) { struct acpi_device *d; if (acpi_bus_get_device(obj_handle, &d)) return 0; *return_value = acpi_driver_data(d); return 1; } /* VIA don't support PM2 reg, but have something similar */ static int enable_arbiter_disable(void) { struct pci_dev *dev; int status = 1; int reg; u8 pci_cmd; /* Find PLE133 host bridge */ reg = 0x78; dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8601_0, NULL); /* Find PM133/VT8605 host bridge */ if (dev == NULL) dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8605_0, NULL); /* Find CLE266 host bridge */ if (dev == NULL) { reg = 0x76; dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_862X_0, NULL); /* Find CN400 V-Link host bridge */ if (dev == NULL) dev = pci_get_device(PCI_VENDOR_ID_VIA, 0x7259, NULL); } if (dev != NULL) { /* Enable access to port 0x22 */ pci_read_config_byte(dev, reg, &pci_cmd); if (!(pci_cmd & 1<<7)) { pci_cmd |= 1<<7; pci_write_config_byte(dev, reg, pci_cmd); pci_read_config_byte(dev, reg, &pci_cmd); if (!(pci_cmd & 1<<7)) { printk(KERN_ERR PFX "Can't enable access to port 0x22.\n"); status = 0; } } pci_dev_put(dev); return status; } return 0; } static int longhaul_setup_southbridge(void) { struct pci_dev *dev; u8 pci_cmd; /* Find VT8235 southbridge */ dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8235, NULL); if (dev == NULL) /* Find VT8237 southbridge */ dev = pci_get_device(PCI_VENDOR_ID_VIA, PCI_DEVICE_ID_VIA_8237, NULL); if (dev != NULL) { /* Set transition time to max */ pci_read_config_byte(dev, 0xec, &pci_cmd); pci_cmd &= ~(1 << 2); pci_write_config_byte(dev, 0xec, pci_cmd); pci_read_config_byte(dev, 0xe4, &pci_cmd); pci_cmd &= ~(1 << 7); pci_write_config_byte(dev, 0xe4, pci_cmd); pci_read_config_byte(dev, 0xe5, &pci_cmd); pci_cmd |= 1 << 7; pci_write_config_byte(dev, 0xe5, pci_cmd); /* Get address of ACPI registers block*/ pci_read_config_byte(dev, 0x81, &pci_cmd); if (pci_cmd & 1 << 7) { pci_read_config_dword(dev, 0x88, &acpi_regs_addr); acpi_regs_addr &= 0xff00; printk(KERN_INFO PFX "ACPI I/O at 0x%x\n", acpi_regs_addr); } pci_dev_put(dev); return 1; } return 0; } static int longhaul_cpu_init(struct cpufreq_policy *policy) { struct cpuinfo_x86 *c = &cpu_data(0); char *cpuname = NULL; int ret; u32 lo, hi; /* Check what we have on this motherboard */ switch (c->x86_model) { case 6: cpu_model = CPU_SAMUEL; cpuname = "C3 'Samuel' [C5A]"; longhaul_version = TYPE_LONGHAUL_V1; memcpy(mults, samuel1_mults, sizeof(samuel1_mults)); memcpy(eblcr, samuel1_eblcr, sizeof(samuel1_eblcr)); break; case 7: switch (c->x86_mask) { case 0: longhaul_version = TYPE_LONGHAUL_V1; cpu_model = CPU_SAMUEL2; cpuname = "C3 'Samuel 2' [C5B]"; /* Note, this is not a typo, early Samuel2's had * Samuel1 ratios. */ memcpy(mults, samuel1_mults, sizeof(samuel1_mults)); memcpy(eblcr, samuel2_eblcr, sizeof(samuel2_eblcr)); break; case 1 ... 15: longhaul_version = TYPE_LONGHAUL_V2; if (c->x86_mask < 8) { cpu_model = CPU_SAMUEL2; cpuname = "C3 'Samuel 2' [C5B]"; } else { cpu_model = CPU_EZRA; cpuname = "C3 'Ezra' [C5C]"; } memcpy(mults, ezra_mults, sizeof(ezra_mults)); memcpy(eblcr, ezra_eblcr, sizeof(ezra_eblcr)); break; } break; case 8: cpu_model = CPU_EZRA_T; cpuname = "C3 'Ezra-T' [C5M]"; longhaul_version = TYPE_POWERSAVER; numscales = 32; memcpy(mults, ezrat_mults, sizeof(ezrat_mults)); memcpy(eblcr, ezrat_eblcr, sizeof(ezrat_eblcr)); break; case 9: longhaul_version = TYPE_POWERSAVER; numscales = 32; memcpy(mults, nehemiah_mults, sizeof(nehemiah_mults)); memcpy(eblcr, nehemiah_eblcr, sizeof(nehemiah_eblcr)); switch (c->x86_mask) { case 0 ... 1: cpu_model = CPU_NEHEMIAH; cpuname = "C3 'Nehemiah A' [C5XLOE]"; break; case 2 ... 4: cpu_model = CPU_NEHEMIAH; cpuname = "C3 'Nehemiah B' [C5XLOH]"; break; case 5 ... 15: cpu_model = CPU_NEHEMIAH_C; cpuname = "C3 'Nehemiah C' [C5P]"; break; } break; default: cpuname = "Unknown"; break; } /* Check Longhaul ver. 2 */ if (longhaul_version == TYPE_LONGHAUL_V2) { rdmsr(MSR_VIA_LONGHAUL, lo, hi); if (lo == 0 && hi == 0) /* Looks like MSR isn't present */ longhaul_version = TYPE_LONGHAUL_V1; } printk(KERN_INFO PFX "VIA %s CPU detected. ", cpuname); switch (longhaul_version) { case TYPE_LONGHAUL_V1: case TYPE_LONGHAUL_V2: printk(KERN_CONT "Longhaul v%d supported.\n", longhaul_version); break; case TYPE_POWERSAVER: printk(KERN_CONT "Powersaver supported.\n"); break; }; /* Doesn't hurt */ longhaul_setup_southbridge(); /* Find ACPI data for processor */ acpi_walk_namespace(ACPI_TYPE_PROCESSOR, ACPI_ROOT_OBJECT, ACPI_UINT32_MAX, &longhaul_walk_callback, NULL, NULL, (void *)&pr); /* Check ACPI support for C3 state */ if (pr != NULL && longhaul_version == TYPE_POWERSAVER) { cx = &pr->power.states[ACPI_STATE_C3]; if (cx->address > 0 && cx->latency <= 1000) longhaul_flags |= USE_ACPI_C3; } /* Disable if it isn't working */ if (disable_acpi_c3) longhaul_flags &= ~USE_ACPI_C3; /* Check if northbridge is friendly */ if (enable_arbiter_disable()) longhaul_flags |= USE_NORTHBRIDGE; /* Check ACPI support for bus master arbiter disable */ if (!(longhaul_flags & USE_ACPI_C3 || longhaul_flags & USE_NORTHBRIDGE) && ((pr == NULL) || !(pr->flags.bm_control))) { printk(KERN_ERR PFX "No ACPI support. Unsupported northbridge.\n"); return -ENODEV; } if (longhaul_flags & USE_NORTHBRIDGE) printk(KERN_INFO PFX "Using northbridge support.\n"); if (longhaul_flags & USE_ACPI_C3) printk(KERN_INFO PFX "Using ACPI support.\n"); ret = longhaul_get_ranges(); if (ret != 0) return ret; if ((longhaul_version != TYPE_LONGHAUL_V1) && (scale_voltage != 0)) longhaul_setup_voltagescaling(); policy->cpuinfo.transition_latency = 200000; /* nsec */ return cpufreq_table_validate_and_show(policy, longhaul_table); } static struct cpufreq_driver longhaul_driver = { .verify = cpufreq_generic_frequency_table_verify, .target_index = longhaul_target, .get = longhaul_get, .init = longhaul_cpu_init, .name = "longhaul", .attr = cpufreq_generic_attr, }; static const struct x86_cpu_id longhaul_id[] = { { X86_VENDOR_CENTAUR, 6 }, {} }; MODULE_DEVICE_TABLE(x86cpu, longhaul_id); static int __init longhaul_init(void) { struct cpuinfo_x86 *c = &cpu_data(0); if (!x86_match_cpu(longhaul_id)) return -ENODEV; if (!enable) { printk(KERN_ERR PFX "Option \"enable\" not set. Aborting.\n"); return -ENODEV; } #ifdef CONFIG_SMP if (num_online_cpus() > 1) { printk(KERN_ERR PFX "More than 1 CPU detected, " "longhaul disabled.\n"); return -ENODEV; } #endif #ifdef CONFIG_X86_IO_APIC if (cpu_has_apic) { printk(KERN_ERR PFX "APIC detected. Longhaul is currently " "broken in this configuration.\n"); return -ENODEV; } #endif switch (c->x86_model) { case 6 ... 9: return cpufreq_register_driver(&longhaul_driver); case 10: printk(KERN_ERR PFX "Use acpi-cpufreq driver for VIA C7\n"); default: ; } return -ENODEV; } static void __exit longhaul_exit(void) { struct cpufreq_policy *policy = cpufreq_cpu_get(0); int i; for (i = 0; i < numscales; i++) { if (mults[i] == maxmult) { struct cpufreq_freqs freqs; freqs.old = policy->cur; freqs.new = longhaul_table[i].frequency; freqs.flags = 0; cpufreq_freq_transition_begin(policy, &freqs); longhaul_setstate(policy, i); cpufreq_freq_transition_end(policy, &freqs, 0); break; } } cpufreq_cpu_put(policy); cpufreq_unregister_driver(&longhaul_driver); kfree(longhaul_table); } /* Even if BIOS is exporting ACPI C3 state, and it is used * with success when CPU is idle, this state doesn't * trigger frequency transition in some cases. */ module_param(disable_acpi_c3, int, 0644); MODULE_PARM_DESC(disable_acpi_c3, "Don't use ACPI C3 support"); /* Change CPU voltage with frequency. Very useful to save * power, but most VIA C3 processors aren't supporting it. */ module_param(scale_voltage, int, 0644); MODULE_PARM_DESC(scale_voltage, "Scale voltage of processor"); /* Force revision key to 0 for processors which doesn't * support voltage scaling, but are introducing itself as * such. */ module_param(revid_errata, int, 0644); MODULE_PARM_DESC(revid_errata, "Ignore CPU Revision ID"); /* By default driver is disabled to prevent incompatible * system freeze. */ module_param(enable, int, 0644); MODULE_PARM_DESC(enable, "Enable driver"); MODULE_AUTHOR("Dave Jones"); MODULE_DESCRIPTION("Longhaul driver for VIA Cyrix processors."); MODULE_LICENSE("GPL"); late_initcall(longhaul_init); module_exit(longhaul_exit);